In a Human-Robot Interactive (HRI) system, a human operator interfaces directly with a robotic device that, by applying a force to one or more linkages, performs or assists in the performance of a particular task. The operator may apply input in the form of an applied force and/or torque, which a controller must interpret in relation to the task that is being performed. By doing so, the robot as well as the operator form an integrated system which performs the desired tasks. As one of two parts in the system, the robot must be able to work effectively with the human. Therefore, it is a basic goal of any HRI system to accurately define a human model, typically in the form of operating principles and/or control algorithms, allowing for a more natural and effective interaction between the human operator(s) and the various integrated components of the robot.